The present invention relates to apparatus for automatically folding paper-like sheets of material, and more particularly, to an apparatus for folding one or more paper sheets into three sections in preparation for mailing in an envelope.
There are many instances in which sheets of paper are to be folded for insertion into envelopes for subsequent mailing. Specifically, it is often desirable to fold one or several letter size sheets into three equal sections for insertion into a standard mailing envelope. It is often important from the viewpoint of efficiency, time saving and minimizing of costs to effect such folding as rapidly and easily as possible.
A variety of machines are known which can accomplish such folding automatically when fed sequentially with individual sheets or sets of sheets of paper. However, such machines tend to be rather complex and expensive, and hence are not best suited for ordinary light office use.
U.S. Pat. No. 5,147,275 to the same inventor herein, and the entire disclosure of which is incorporated herein by reference discloses an automatic paper feeder that overcomes the aforementioned disadvantages. In this patent, the paper is guided into a loop so that the leading edge of the sheet strikes the trailing portion of the paper to create a fold thereat. Then, the leading edge and the folded trailing portion enter a nip between two rollers upon continued feeding of the paper, in order to fold the paper into three sections. However, the force of the leading edge of the sheet against the trailing portion in order to create the fold thereat is the result merely by the feeding of the paper into the device, which may not be entirely satisfactory. In other words, there is no positive forcing of the leading edge into the trailing portion of the sheet, but rather, merely the indirect force due to the initial feed of the paper into the device.
In addition, the device of this patent relies on a paper guide that is spring loaded and which expands against spring pressure, due to the force of the loop of paper, in order to permit additional paper to enter the device, after the leading edge of the sheet strikes its own trailing portion, and then when the leading edge and folded portion enter the nip, the spring pressure exerts a force on the guide to further aid in forcing the sheet further into the nip between the rollers. Again, this is an inexact manner of forcing the paper into the nip. The use of a spring loaded guide also increases the complexity of the device.
Still further, the last part of the paper to enter the nip is the loop of paper that had been guided by the paper guide. As this last loop of paper enters the nip, a second fold is formed. However, as the loop reduces in size and disengages from the paper guide, there is nothing to guide the paper. As a result, problems in the folding of this last loop can occur.
Still further, with the device of this patent, there are often problems with feeding of the paper at the entry port. Specifically, when loading a stack of papers, a plurality of papers will often be carried into the device at the same time, rather than separating the papers to supply them one at a time.
Lastly, there is no structure at the output for guiding and/or holding the folded sheets of paper.
Accordingly, it is an object of the present invention to provide a new and useful apparatus for folding sheets of paper-like materials that overcomes the aforementioned disadvantages.
It is another object of the present invention to provide a new and useful apparatus for folding sheets of paper-like materials in which there is an arrangement for providing a positive force of the leading edge into the trailing portion of the sheet.
It is still another object of the present invention to provide a new and useful apparatus for folding sheets of paper-like materials in which the positive force is created by additional driving rollers associated with the leading edge and which are driven by the input drive rollers.
It is yet another object of the present invention to provide a new and useful apparatus for folding sheets of paper-like materials in which the paper guide is fixed in place in order to simplify the construction.
It is a further object of the present invention to provide a new and useful apparatus for folding sheets of paper-like materials in which the same driving rollers associated with the leading edge also function to guide the reduced loop to form the second fold.
It is still a further object of the present invention to provide a new and useful apparatus for folding sheets of paper-like materials which effectively separates the papers at the entry port to supply them one at a time.
It is yet a further object of the present invention to provide a new and useful apparatus for folding sheets of paper-like materials which includes a paper stocker at the output for guiding and holding the folded papers.
It is another object of the present invention to provide a new and useful apparatus for folding sheets of paper-like materials which is relatively simple, inexpensive and easy to use.
In accordance with an aspect of the present invention, a paper folder for folding a paper-like sheet, includes a housing having an inlet opening for receiving a paper-like sheet and an outlet opening for permitting egress of a fully folded paper-like sheet; an input drive arrangement in the housing which advances a paper-like sheet from said inlet opening into said housing; a fixed guide in the housing which guides said advancing sheet into a loop that turns back upon itself such that a leading edge of said sheet impinges upon a transverse line in a trailing portion of said sheet; an output roller arrangement in the housing which forms a folding nip extending along and adjacent to said transverse line; and a second drive arrangement in the housing in front of said transverse line for positively driving the leading edge of said sheet to impinge upon said transverse line, such that the second drive arrangement continually advances said leading edge against said transverse line in said trailing portion of said sheet to force both said leading edge of said sheet and said transverse line in said sheet into said folding nip in order to form a first creased fold in said sheet extending along said transverse line and containing said sheet leading edge, said second drive arrangement being separate and apart from said fixed guide; whereby, upon further operation, said leading edge of said sheet remains within and travels with said fold as said fold passes through said folding nip, and a remaining portion of said sheet extending in a loop thereafter passes through said folding nip to form a second creased fold, thereby folding said sheet into a fully folded paper-like sheet having three sections and supplying said fully folded paper-like sheet to said outlet opening in said housing.
The second drive arrangement includes a pair of rollers having a nip therebetween for engaging the leading edge and driving the leading edge to impinge upon the transverse line. The pair of rollers includes an idler roller and at least one pinch roller, with each pinch roller being mounted on a shaft which is pivotally movable between a first position in which the pinch roller is in pressure contact with the idler roller to advance the leading edge, and to a second position in which the pinch roller is moved out of the path of the loop in order to permit the loop to enter the output roller arrangement. Preferably, there are two the pinch rollers at opposite sides of the housing for engaging opposite sides of the leading edge. The second drive arrangement further includes a spring associated with each pinch roller for biasing each pinch roller toward the first position, and wherein each pinch roller is moved to the second position by a force exerted by the loop as the loop moves toward the output roller arrangement, against the force of the respective spring. In addition, the second drive arrangement is driven by the input drive arrangement.
The guide is fixed in position and is formed by inner walls of the housing. Specifically, the housing includes a base having a rear wall, side walls, a bottom wall with an inverted V-shaped projection and curved front wall, and a cover having a curved front wall which forms a continuation of the curved front wall of the base; and the guide is formed by the V-shaped projection, the curved front wall of the base and the curved front wall of the cover.
The input drive arrangement includes an input drive roller and an idler roller forming an input nip therebetween; and the output roller arrangement includes an output roller forming the folding nip with the input drive roller.
A mechanical sensor is provided for sensing when the sheet is in the folder. In this regard, a drive motor operates the input drive arrangement, and a switch is operated by the mechanical sensor to turn the motor on when a sheet enters the folder and to turn the motor off when the sheet has exited the folder.
In accordance with another aspect of the present invention, a paper folder for folding a paper-like sheet, includes a housing having an inlet opening for receiving a paper-like sheet and an outlet opening for permitting egress of a fully folded paper-like sheet; an input drive arrangement in the housing which advances a paper-like sheet from the inlet opening into the housing; a guide in the housing which guides the advancing sheet into a loop that turns back upon itself such that a leading edge of the sheet impinges upon a transverse line in a trailing portion of the sheet; an output roller arrangement in the housing which forms a folding nip extending along and adjacent to the transverse line, such that as the leading edge continually advances against the transverse line in the trailing portion of the sheet, the leading edge and the transverse line are forced into the folding nip in order to form a first creased fold in the sheet extending along the transverse line and containing the sheet leading edge and upon further operation, a remaining portion of the sheet extending in a loop passes through the folding nip to form a second creased fold, thereby folding the sheet into a fully folded paper-like sheet having three sections and supplying the fully folded paper-like sheet to the outlet opening in the housing; and a stocker mounted on an outside wall of the housing adjacent to the outlet opening for stocking a plurality of the fully folded paper-like sheets.
The stocker includes a bent rod having a first section that extends into the housing; and a downwardly angled section connected with the first section and which is spaced slightly from the housing; and a spring within the housing for biasing the first section such that the downwardly angled section is pivoted towards the housing and the fully folded sheets are held by the downwardly angled section with a spring force.
In accordance with still another aspect of the present invention, a paper folder for folding a paper-like sheet, including a housing having an inlet opening for receiving a paper-like sheet and an outlet opening for permitting egress of a fully folded paper-like sheet; an input paper tray for providing a stack of the paper-like sheets such that lower edges thereof are positioned adjacent the inlet opening; an input drive arrangement in the housing which advances a paper-like sheet from the inlet opening into the housing, the input drive arrangement including an input drive roller arrangement having a circumferential gap, and an idler roller forming an input nip with the input drive roller arrangement; a flexible stripper pad of high friction material positioned at the circumferential gap; a guide in the housing which guides the advancing sheet into a loop that turns back upon itself such that a leading edge of the sheet impinges upon a transverse line in a trailing portion of the sheet; an output roller arrangement in the housing which forms a folding nip extending along and adjacent to the transverse line, such that as the leading edge continually advances against the transverse line in the trailing portion of the sheet, the leading edge and the transverse line are forced into the folding nip in order to form a first creased fold in the sheet extending along the transverse line and containing the sheet leading edge and upon further operation, a remaining portion of the sheet extending in a loop passes through the folding nip to form a second creased fold, thereby folding the sheet into a fully folded paper-like sheet having three sections and supplying the fully folded paper-like sheet to the outlet opening in the housing.
In one embodiment, the input drive roller arrangement includes a single input drive roller having a circumferential groove which forms the circumferential gap. In another embodiment, the input drive roller arrangement includes two coaxial, spaced apart drive rollers having the circumferential gap therebetween.
In addition, a fixed beam is positioned in front of a lower portion of the paper tray, with the flexible stripper pad being secured to the fixed beam at a position of the circumferential gap. An adjusting screw extends through the fixed beam to adjust a position of the stripper pad relative to the input drive arrangement in order to adjust a gap between the input drive arrangement and the stripper pad.
There is also a spring gate secured to the fixed beam between the stripper pad and the fixed beam.